The width of an agricultural vehicle has an impact on the capacity that can be obtained from the machine. A trend in the design of agricultural vehicles, especially combines and other equipment used to traverse a field, is for the size of the machines to become larger, reducing the number of passes required to cover a field. Agricultural harvesters, such as combines, include a header and a feeder housing which remove the crop material from the field, gather the crop material and transport the crop material to a separator in the harvester. The separator removes the grain crop material from the non-grain crop material, also known as residue. As the width of the header of the harvester is increased, more crop material can be processed and harvested. As a result, it is necessary to increase the capacity of processing equipment and crop storage bins on the harvester body. The supporting structure, including the frame and wheels, must be enlarged to provide the necessary stability for the overall larger size of the equipment. On the field, it is therefore found necessary to increase the track width of the vehicle to provide the necessary stability. However, the track width for driving on the public roads is limited by legislations in many countries.
EP 2 168 786 describes an axle for an agricultural vehicle such as a combine, with a variable track width. A drawback of the described system is that the maximum turning angle in a narrow track width position is limited.